一株具杀褐飞虱活性银杏内生真菌的研究

发布时间：2018-06-26 17:28

  本文选题：银杏 + 内生真菌　； 参考：《福建农林大学》2015年硕士论文

【摘要】：植物内生真菌(Endophytic Fungus)与植物长期协同进化的过程中能够产生与宿主植物相同或相似的活性物质,植物内生真菌在农业和医药研究上已得到广泛应用。本论文从传统的中药材植物银杏(Ginkgo biloba)中分离筛选具杀褐飞虱(Nilaparvata lugens(Stal))活性的植物内生真菌为主线,为下一步分离鉴定活性物质提供材料。主要结果如下：1.从银杏叶、短枝和根部共分离出内生真菌172株。其中,短枝中分离得到内生真菌最多,达78株,占分离总数的45.35%；根部次之,占总数的38.37%；而叶片中仅分离出28株菌,占总数的16.28%。2.以褐飞虱作为靶标昆虫,采用点背法进行具杀虫活性内生真菌初步筛选,结果发现有FC-5-3、FP-8-1、JP-6-2、JP-5-1、JP-11、JP-6-5、NP-5-3、NP-2-2、 NC-3-3等9株内生真菌具有较好的触杀活性。其中活性最好的JP-6-2菌株48h校正死亡率高达97.69%,LCso为0.44mg/ml。3.为了明确JP-6-2菌株代谢产物中杀虫活性物质的理化性质,测定了该物质在紫外光照、高温及室外环境条件的稳定性,测试结果表明：该杀虫活性物质在高温下比较稳定,具有较好的耐热性,但在紫外光、室外环境条件下稳定较差。4.通过对该菌株进行菌丝体、孢子形态和ITS鉴定,表明JP-6-2菌株属于链格孢属(Altermaria.sp),可能属于细极链格孢种(Altermaria tenuissima),并构建了系统发育树研究其种属地位。5.论文通过考察多个单因素和采用正交实验方法来优化菌株发酵条件,最终优化结果是：蔗糖30.00g/L,尿素2.00g/L,磷酸氢二钾4.00g/L,硫酸镁1.00g/L,硫酸亚铁0.01g/L氯化钾0.50g/L,每摇瓶装液量50.0ml/250ml,种子液接种量120.0ml/1L,温度27.0℃,转速200r/min,初始pH值8.5,发酵培养时间9d。粗提物重量达到0.456g/L,增加237.78%；LC50达到0.58mg/ml,增加31.82%。
[Abstract]:Endophytic Fungus (endophytic Fungus) can produce the same or similar active substances as host plants during long-term coevolution. Plant endophytic fungi have been widely used in agricultural and medical research. In this paper, endophytic fungi with the activity of Nilaparvata lugens (Stal) were isolated and screened from the traditional Chinese medicinal plant ginkgo biloba as the main line to provide materials for the further isolation and identification of active substances. The main results are as follows: 1. 172 strains of endophytic fungi were isolated from leaves, short branches and roots of Ginkgo biloba. The endophytic fungi isolated from the short branches were the most, accounting for 78 strains, accounting for 45.35% of the total, followed by the roots, accounting for 38.37% of the total, while only 28 strains were isolated from the leaves, accounting for 16.28.2% of the total. The primary screening of endophytic fungi with insecticidal activity was carried out using brown planthopper as target insect. The results showed that 9 endophytic fungi such as FC-5-3, FP-8-1, JP-6-1, JP-11JP-6-5, NP-5-3NP-2-2 and NC-3-3 had good contact killing activity. Among them, the best JP-6-2 strain had a 48h adjusted mortality of 97.69% LCso of 0.44 mg / ml. 3. In order to determine the physical and chemical properties of the insecticidal active substance in the metabolites of JP-6-2 strain, the stability of the substance in ultraviolet light, high temperature and outdoor environment was determined. The results showed that the insecticidal active substance was stable at high temperature. It has good heat resistance, but it is less stable in ultraviolet light and outdoor environment. The identification of mycelia, spore morphology and its showed that JP-6-2 belonged to Altermaria.sp, which may belong to (Altermaria tenuissima), and constructed phylogenetic tree to study its genus status. In this paper, the fermentation conditions of the strain were optimized by investigating several single factors and adopting the orthogonal experiment method. The optimized results were as follows: sucrose 30.00g / L, urea 2.00g / L, potassium hydrogen phosphate 4.00g / L, magnesium sulfate 1.00g / L, ferrous sulfate 0.01g / L potassium chloride 0.50g / L, inoculation amount of seed liquid 120.0ml / L, temperature 27.0 鈩，

本文编号：2070818